Old Clubhouse Closure & Future Direction

FROM CLUB’S ANNUAL GENERAL MEETING

27TH OCTOBER 2020

CLOSURE FOR SAFETY CONCERNS

The Old Clubhouse has shown signs of structural erosion and depreciation over the years and recent load tests have led to expert analysis that has concluded that the building is currently unsafe for daily usage and operations. Thus, the decision has been made to immediately close the building at the end of this month in order to ensure the safety of members, staff and guests.

NEXT STEPS

As mentioned at the recent AGM, all members will soon be called upon to actively participate in deciding the future of our Old Clubhouse, be it a minor or major renovation, or complete rebuild. Firstly, a survey will be sent to gather ideas so that the management better understands the overall membership needs. We greatly need everyone’s feedback so that the management may best address key concerns moving forward.

Executive Summary

(Data provided by STS Group)

Structural Investigation and Stability Analysis

THE ROYAL BANGKOK SPORTS CLUB

Henri Dunant Rd., Bangkok

(From year 2010-2020)

    The existing club building at the Royal Bangkok Sports Club (RBSC) has been investigated to evaluate the stability of all structure members by finite element method on year 2010 & year 2017. In addition, the preliminary condition survey had been performed last year (year 2019) to record the progress of all physical defects as well as structure behavior compared to the previous records.

    The results can be summarized as follows;

1. Structural Systems

The existing club building is a 2-storey building with 37×90 m size. The structure includes multi-structural systems i.e. reinforced concrete (R/C) structures, masonry walls, wood structures, steel structures, which can be briefly summarized as:-

2. Physical Damage

    The current physical damage (Defect), found on this inspection (year 2019), were summarized in Fig 01 below.

Physical damage plan – 1st FLOOR

Physical damage plan – 1st FLOOR

Physical damage plan – 2nd FLOOR

Physical damage plan – 2nd FLOOR

Physical damage plan – 2nd FLOOR

Physical damage plan – Ceiling and Roof

Physical damage plan – Ceiling and Roof

Physical damage plan – Ceiling and Roof

Figure 01 Physical damage recorded.

3. Material Strength

    The major construction material ie., concrete, steel rebar, wood and brick wall, were randomly tested by destructive and non-destructive test to evaluate material strength. The results are summarized in Table 01 below.

Table 01 Summary Strength of Material

Material Structure member Strength Type Strength (ksc)
Year 2010 Year 2017 Year 2019
Concrete Column Compressive Strength182179138
BeamCompressive Strength204186144
Slab Compressive Strength219238 233
Reinforcement bar (round bar)  Column & Beam Ultimate Compressive Strength4122-4566
  Wood   Ultimate Compressive Strength   403 – 425  –   –
Ultimate Bending Strength  338 – 835  –  –
Ultimate Shear Strength20 – 47
Brick   WallUltimate Compressive Strength  4.5 – 11.9  –  –
It should be noted that the concrete strength (fc’) are reduce by 2-29% in ten (10) years period.

4. Building Plane

    Inclination plan of ground floor and upper floor, measured on different period are summarized in Table 02 below. In general, the average building plane are stable and within acceptable range (less than 1:300). However, the potential of differential settlement is detected as indicated in Fig 02 and Fig 03 below.

Table 02 Inclination Plan of Club Building

  Floor   Direction Inclination Plan
Year 2010 Year 2017 Year 2019
1 North-South Direction 1:-4721:530 1:530
East-West Direction1:1505 1:4171:417
2 North-South Direction1:-333 1:3151:315
East-West Direction 1:7211:759 1:759

5. Structural Stability

    In year 2017, the detail structure stability analysis has been done to evaluate the actual safe service load. The complete 3-dimensional model of the building, shown in Figure 04, was set up. The analysis was carried out by finite element method using structure program “SAP2000”. Base on the structural analysis results, the safe service live load for ground floor and upper floor slab are advised in Figures 05 and 06, respectively.

Figure 04 3-Dimensional mathematical model
Figure 05 Safe service load on the 1st floor Figure 06
Figure 06 Safe service load on the 2nd floor

Safe service load as recommended above, should be considered the additional comment as follows:

    A) 2nd floor slab in the middle of the building is timber structure (D-G/3-9 and D-G/14-20). Safe service load of these areas are very low. It is recommended to stop using these areas and do not use as stock area.

   B) Safe service load on terrace of 2nd floor (A-D/1-21) area are quite low ( ~100kg./ sq.m.). It is strongly recommended to control amount of people to use this area (especially on horse racing time) not more than the recommended service load as above.

    C) Safe service load of 2nd floor, D-G/9-11 and D-G/12-14 area are quite low (̴ 100 kg./ sq.m.). It is strongly recommended to control amount of people to use this area not more than the recommended service load as above.

    D) Safe service load of 2nd floor I-G/1-21 and D-G/20-21 area are quite low (̴ 100 kg./ sq.m.). It is strongly recommended to control amount of people to use this area not more than the recommended service load as above.

6. Building Condition Classification

    In year 2019, the detail structure analysis was not performed. However the structure stability was evaluated by the visual condition and the above field survey & testing based on the criteria modified from the recommendation of Burland et, al, 2001 (Building Damage Classification) are shown in Table 03 below.

Table 03 Degree of damage

Degree of Damage Risk Category Overall Condition
Moderate – Severe 3-4The overall current structure stability may be lower than the standard requirement

 

7. Conclusion and Comments

    7.1 At present (year 2019), the clubhouse building was classified in “Moderate-Severe” degree of damage based on the criteria modified from Burland et, al, 2001 recommendation. In these categories, the current overall structure stability may lower than the standard requirement. It is recommended to consider as follow.

       7.1.1 Confirm the stability of each structure members by details structure analysis, similar to the report on year 2017.

      7.1.2 All insufficient capacity member, indicated by the analysis result in clause 7.1.1 shall be strengthened by proper method.

        7.1.3 During the period, waiting for the result on clause 7.1.1, the safe service load on each part of the building shall be limited as specified in report on year 2017 or as mentioned in Fig 05 and Fig 06.

   7.2 All physical distresses, found and recorded in table 1, shall be rectified by proper method or as suggested below.

       7.2.1 Concrete spalling and/or rebar corroded exposed (distress type 1) are assumed to be caused by corrosion of rebar. It is recommended to repair by conventional patch and repair (CPR). The detail method of repair can be referred to Standard No. 1901-51 (Concrete Repair Standard) issued by Department of Public Works and Town & Country Planning, Ministry of Interior as described below.

       7.2.2 Crack lines on bottom of slab (distress type 2&3) are assumed to be caused by deflection of slab, these crack lines should be filled by epoxy injection method referred to Standard No. 1901-51 (Concrete Repair Standard) for integrity of slab section and serviceability in long term.

       7.2.3 Crack lines on top of slab along the position of beam or bearing wall underneath (distress type 4) are assumed caused by excess negative moment over support area. It is recommended to install dowel bar every 20 cm. to improve the moment capacity of slab before patching with high elastic plaster material.

       7.2.4 Crack lines on top in the middle of slab (distress type 5) are assumed to be caused by plastic shrinkage. It is recommended to fill all crack lines where crack width more than 0.3 mm. by epoxy injection method under low pressure grouting.

       7.2.5 The crack lines found in the middle zone of wall (distress type 6), it is recommended to repair by stitching method. V-groove about 10 cm width shall be prepared along the crack lines. Install Ø 4 mm wire every 0.15 m (Ø 4 mm wire @0.15 m) perpendicular to crack lines. After that, fill the groove line with high elastic plaster material.

   7.3 Long term settlement monitoring is recommended to carry out at least once a year in order to observe the progress of differential settlement which found in the north wing of the building.

Executive Summary

(Data provided by STS Group)

Floor Load Test of The 2nd Floor Slab at GL. D-G/12-14 and A-C/11-15

Existing Clubhouse building, RBSC    

1. Test results of Slab-Beam systems on 2nd floor at GL. D-G/12-14

    The results of floor load test of the reinforced concrete (R/C) slab-beam systems at the 1st test area on the 2nd floor at GL. D-G/12-14 subjected to the maximum test load 290 kg/sq.m. (Equivalent to live load 150 kg/sq.m. + super-imposed dead load 5 kg/sq.m.) indicates that the R/C slab-beam systems is capable to resist the equivalent live load level satisfying the deflection criteria as per the test standard.   

    However, the overall structural systems at this location consists of the R/C slab-beams supported by bearing wall structures at perimeter of the test area (Gl. D, G, 12 and 14). The structural stability analysis, as per the report on structure stability evaluation since April, 2017, revealed that the masonry bearing wall was capable to resist the service live load as 95 kg/sq.m. on the entire service area. It implied that the service live load on the 2nd floor slab at this position was limited by capacity of the bearing wall structures.

    This floor load test aimed to evaluate the structural behavior of the slab-beams system within the test area, thereby the results were reasonably applicable for the test structures.

    Besides, for actual usages, if there is a plan to re-allocate various service functions on each area, for examples, “consider to use the service live load as 150 kg/sq.m. on the 2nd floor slab at Gl. D-G/12-14 and limit the service usage on the area around this location to 50 – 75 kg/sq.m. to reduce the loading supported by the bearing wall structures.” This will be beneficial to the function arrangement planning.

2. Test results of Slab-Beam systems on 2nd floor at GL. A-C/11-15

    The results of floor load test of the reinforced concrete (R/C) slab-beam systems at the 2nd test area on the 2nd floor at GL. A-C/11-15 subjected to the maximum test load 310 kg/sq.m. (Equivalent to live load 150 kg/sq.m. + super-imposed dead load 80 kg/sq.m.) indicates that the R/C slab-beam systems is capable to resist the equivalent live load level satisfying the deflection criteria as per the test standard.

    However, the overall structural systems at this location consists of the R/C slab-beams supported by R/C column structures at beam intersections on perimeter of the test area (Gl. A and C). The structural stability analysis, as per the report on structure stability evaluation since April, 2017, revealed that the R/C columns was capable to resist the service live load as 91 kg/sq.m. on the entire service area. It implied that the service live load on the 2nd floor slab at this position was limited by capacity of the R/C column structures.

    This floor load test aimed to evaluate the structural behavior of the slab-beams system within the test area, thereby the results were reasonably applicable for the test structures.

    Besides, similarly to the 1st test area for actual usages, if there is a plan to re-allocate various service functions on each area, for examples, “consider to use the service live load as 150 kg/sq.m. on the 2nd floor slab at Gl. A-C/11-15 and limit the service usage on the area around this location to 50 – 75 kg/sq.m. to reduce the loading supported by the R/C column structures.” This will be beneficial to the function arrangement planning.

The Club has consulted with an engineering expert from Faculty of Engineering, Chulalongkorn University for the second opinion and the recommendations are as follows:

    1. To limit the usage of the old clubhouse and install the protection equipment at dangerous zones

    2. To construct new clubhouse to replace the old one

    3. To repair the whole structure of the old clubhouse before resuming usage if the Club continues to use the old clubhouse as usual.

 

Investigation works timeline

Clubhouse building, RBSC

Detail of Study Date
Preliminary building condition survey, stage include Physical condition inspection, material strength testing building plane survey, column verticality checking carbonation test, Floor load test and structure damage classification base on Burland et al 2001   Dec, 2006 (ธันวาคม 2549)
Installation of Long term settlement marks included initial reading (April 3rd ,2017)   Apr, 2007 (เมษายน 2550)
Long term settlement monitoring
1st reading (Oct 2nd ,2007)
2nd reading (April 4th ,2008)
3rd reading (Oct 16th ,2008)
4th reading (Nov 16th ,2009)
Oct, 2007 (ตุลาคม 2550)
May, 2008 (พฤษภาคม 2551)
Dec, 2008 (ธันวาคม 2551)
Dec, 2009 (ธันวาคม 2552)

Investigation works timeline

Clubhouse building, RBSC

Detail of Study Date
  Structure investigation and Stability Analysis on The Existing Structures of Clubhouse Building, The Royal Bangkok Sports Club. (Building Condition Survey Stage II) Included Material Strength Testing, Structural detail survey, plane leveling survey, structural stability analysis   May 2010 (พฤษภาคม 2553)
  Building condition survey, stage include Physical condition survey, Building plane survey, material strength testing, Deflection survey of beam and slab, verticality of column, carbonation test and structure stability Analysis   Apr, 2017 (เมษายน 2560)
  Preliminary Building Condition Assessment (Building Condition Survey Stage I) including Visual inspection & distress condition mapping, building plane survey, concrete strength testing.  January 2020 (มกราคม 2563)
  Results of full-scale load testing for 2nd floor slab at GL. D-G/12-14 & A-C/    11-15 subjected to equivalent live load 150 ksm. March 2020 (มีนาคม 2563)

Floor Load Test

 

     Moisture Stains

 

Concrete Spalling

 

Concrete Deterioration

 

Concrete Cracks (Floor)

 

Concrete Cracks (Pillars)

 

Exposed Rebar Corrosion

 

ALTERNATIVES

Currently, the General Committee is preparing the relocation plan and timeframe for relocating all the facilities at the old Clubhouse to the NEW locations.

Food & Beverage

No. Current Facilities New Locations Operating Hours
1 Dining Room Winning Post (with limited menu) 6:00 a.m. – 10:00 p.m.
*1st Dec 2020
2 Fast Food
3 Verandah Bar
4 Air Conditioned Bar The Committee box 10:00 a.m. – 11:00 p.m.
*9th Dec 2020
5 Bakery Café Tea Room at RSC Building and additional outlet at Grass Court café 7:00 a.m. – 8:00 p.m.
*1st Dec 2020

Concessionaires

No. Current Facilities New Locations Operating Hours
6 Beauty Salon (Success) Building at Gate 3 7:00 a.m. – 8:00 p.m.
*4th Dec 2020
7 Foot Massage Building at Gate 3 8:00 a.m. – 8:00 p.m.
*4th Dec 2020
8 Relaxation Room Closed during renovation

Others

No. Current Facilities New Locations Operating Hours
9 Men’s & Ladies’ Changing Rooms •Closed during renovation
•Members are advised to use nearby changing rooms at Swimming Pools or Sports Pavilion instead
5:30 a.m. – 9:00 p.m.

 

Following the General Committee’s discussion, there are three alternative solutions of the project as follows:

OPTION 1: Minor Repair of the Old Clubhouse:
Repairing and strengthening the damaged structure to restore live load capability to 250 Kg./Sq.m. according to the original structure design.
Estimated budget for structure remedial works is at Baht 40 MB. (Excluded VAT)
Estimated budget for system work, interior and exterior decorations and contingency is at Baht 95 MB.
(Excluded VAT)
Total estimated budget is at Baht 135 MB. (Excluded VAT)

OPTION 2: Major Repair of the Old Clubhouse:
Repairing and strengthening the structure to achieve live load capability of 400 Kg./Sq.m. as required by law.
Estimated Budget for structure remedial works is at Baht 70 MB. (Excluded VAT)
Estimated budget for system work, interior and exterior decorations and contingency is at Baht 100 MB.
(Excluded VAT)
Total estimated budget is at Baht 170 MB. (Excluded VAT)
Period of work will be around 6 months.

Remark: The difference in budget between Major Repair and Minor Repair options reflect the varying degree of Structural Strengthening required. Estimated cost of Maintenance and Electrical remains the similar amount for both options.

OPTION 3: Construction of New Clubhouse:
In order to construct a new Clubhouse on the current existing area, the Club will have to study and prepare the design and scope of work subject to requirements to project the construction cost.